stk-code_catmod/src/items/network_item_manager.cpp

411 lines
16 KiB
C++

//
// SuperTuxKart - a fun racing game with go-kart
// Copyright (C) 2018 Joerg Henrichs
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 3
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#include "items/network_item_manager.hpp"
#include "karts/abstract_kart.hpp"
#include "modes/world.hpp"
#include "network/network_config.hpp"
#include "network/protocols/game_protocol.hpp"
#include "network/rewind_manager.hpp"
#include "network/stk_host.hpp"
#include "network/stk_peer.hpp"
//-----------------------------------------------------------------------------
/** Creates one instance of the item manager. */
void NetworkItemManager::create()
{
assert(!m_item_manager);
auto nim = std::shared_ptr<NetworkItemManager>(new NetworkItemManager());
nim->rewinderAdd();
m_item_manager = nim;
} // create
// ============================================================================
/** Creates a new instance of the item manager. This is done at startup
* of each race. */
NetworkItemManager::NetworkItemManager()
: Rewinder("N"), ItemManager()
{
m_last_confirmed_item_ticks.clear();
if (NetworkConfig::get()->isServer())
{
auto peers = STKHost::get()->getPeers();
for (auto& p : peers)
{
if (!p->isValidated() || p->isWaitingForGame())
continue;
m_last_confirmed_item_ticks[p] = 0;
}
}
} // NetworkItemManager
//-----------------------------------------------------------------------------
/** Destructor. Cleans up all items and meshes stored.
*/
NetworkItemManager::~NetworkItemManager()
{
for (ItemState* is : m_confirmed_state)
{
delete is;
}
} // ~NetworkItemManager
//-----------------------------------------------------------------------------
void NetworkItemManager::reset()
{
ItemManager::reset();
} // reset
//-----------------------------------------------------------------------------
/** Initialize state at the start of a race.
*/
void NetworkItemManager::initClientConfirmState()
{
m_confirmed_state_time = 0;
m_confirmed_state.clear();
for(auto i : m_all_items)
{
ItemState *is = new ItemState(*i);
m_confirmed_state.push_back(is);
}
} // initClientConfirmState
//-----------------------------------------------------------------------------
/** Called when a kart collects an item. In network games only the server
* acts on this event.
* \param item The item that was collected.
* \param kart The kart that collected the item.
*/
void NetworkItemManager::collectedItem(ItemState *item, AbstractKart *kart)
{
if(NetworkConfig::get()->isServer())
{
// The server saves the collected item as item event info
m_item_events.lock();
m_item_events.getData().emplace_back(World::getWorld()->getTicksSinceStart(),
item->getItemId(),
kart->getWorldKartId() );
m_item_events.unlock();
ItemManager::collectedItem(item, kart);
}
else
{
// The client predicts item collection:
ItemManager::collectedItem(item, kart);
}
} // collectedItem
// ----------------------------------------------------------------------------
/** Called when a new item is created, e.g. bubble gum.
* \param type Type of the item.
* \param kart In case of a dropped item used to avoid that a kart
* is affected by its own items.
*/
Item* NetworkItemManager::dropNewItem(ItemState::ItemType type,
const AbstractKart *kart, const Vec3 *xyz)
{
Item *item = ItemManager::dropNewItem(type, kart, xyz);
if(!item) return NULL;
if (NetworkConfig::get()->isClient())
{
// If this is called when replaying a server event, the calling
// function restoreState will set the item to be not-predicted.
item->setPredicted(true);
return item;
}
// Server: store the data for this event:
m_item_events.lock();
m_item_events.getData().emplace_back(World::getWorld()->getTicksSinceStart(),
type, item->getItemId(),
kart->getWorldKartId(),
kart->getXYZ() );
m_item_events.unlock();
return item;
} // dropNewItem
// ----------------------------------------------------------------------------
/** Called by the GameProtocol when a confirmation for an item event is
* received by the server. Once all hosts have confirmed an event, it can be
* deleted and won't be sent to any clients again.
* \param peer Peer confirming the latest event time received.
* \param ticks Time at which the last event was received.
*/
void NetworkItemManager::setItemConfirmationTime(std::weak_ptr<STKPeer> peer,
int ticks)
{
assert(NetworkConfig::get()->isServer());
if (ticks > m_last_confirmed_item_ticks.at(peer))
m_last_confirmed_item_ticks.at(peer) = ticks;
// Now discard unneeded events and expired (disconnected) peer, i.e. all
// events that have been confirmed by all clients:
int min_time = std::numeric_limits<int32_t>::max();
for (auto it = m_last_confirmed_item_ticks.begin();
it != m_last_confirmed_item_ticks.end();)
{
if (it->first.expired())
{
it = m_last_confirmed_item_ticks.erase(it);
}
else
{
if (it->second < min_time) min_time = it->second;
it++;
}
}
// Find the last entry before the minimal confirmed time.
// Since the event list is sorted, all events up to this
// entry can be deleted.
m_item_events.lock();
auto p = m_item_events.getData().begin();
while (p != m_item_events.getData().end() && p->getTicks() < min_time)
p++;
m_item_events.getData().erase(m_item_events.getData().begin(), p);
m_item_events.unlock();
} // setItemConfirmationTime
//-----------------------------------------------------------------------------
/** Saves the state of all items. This is done by using a state that has
* been confirmed by all clients as a base, and then only adding any
* changes applied to that state later. As clients keep on confirming events
* the confirmed event will be moved forward in time, and older events can
* be deleted (and not sent to the clients anymore).
* This function is also called on the client in the first frame of a race
* to save the initial state, which is the first confirmed state by all
* clients.
*/
BareNetworkString* NetworkItemManager::saveState(std::vector<std::string>* ru)
{
ru->push_back(getUniqueIdentity());
// On the server:
// ==============
m_item_events.lock();
uint16_t n = (uint16_t)m_item_events.getData().size();
if(n==0)
{
BareNetworkString *s = new BareNetworkString();
m_item_events.unlock();
return s;
}
BareNetworkString *s =
new BareNetworkString(n * ( sizeof(int) + sizeof(uint16_t)
+ sizeof(uint8_t) ) );
for (auto p : m_item_events.getData())
{
p.saveState(s);
}
m_item_events.unlock();
return s;
} // saveState
//-----------------------------------------------------------------------------
/** Progresses the time for all item by the given number of ticks. Used
* when computing a new state from a confirmed state.
* \param ticks Number of ticks that need to be simulated.
*/
void NetworkItemManager::forwardTime(int ticks)
{
for(auto &i : m_confirmed_state)
{
if (i) i->update(ticks);
} // for m_all_items
} // forwardTime
//-----------------------------------------------------------------------------
/** Restores the state of the items to the current world time. It takes the
* last saved confirmed state, applies any updates from the server, and
* then syncs up the confirmed state to the in-race items.
* It uses exactly 'count' bytes of the message.
* \param buffer the state content.
* \param count Number of bytes used for this state.
*/
void NetworkItemManager::restoreState(BareNetworkString *buffer, int count)
{
assert(NetworkConfig::get()->isClient());
// The state at World::getTicksSinceStart() needs to be restored. The confirmed
// state in this instance was taken at m_confirmed_state_time. First
// forward this confirmed state to the current time (i.e. world time).
// This is done in several steps:
// 1) First remove all client-side predicted items from the list of all
// items. Predicted item only happen between m_confirmed_state_time
// and 'now'.
// 2) Apply all events included in this state to the confirmed state.
// a) When a collection event is found, adjust the confirmed item state
// only (this state will later be copied to the current item state).
// b) When a new item is created, search in the item cache to see
// if a predicted item for this slot already exists to speed up
// item creation (if not, create a new item). Put this new item
// into the current item state as well as in the confirmed state
// (in the same index position).
// 3) Once all new events have been applied to the confirmed state the
// time must be <= world time. Forward the confirmed state to
// world time, and update m_confirmed_state_time to the world time.
// From here the replay can happen.
// 1) Remove predicted items:
// --------------------------
for (unsigned int i=0; i<m_all_items.size(); i++)
{
Item *item = m_all_items[i];
if(item && item->isPredicted())
{
deleteItem(item);
}
} // for i in m_all_items
// 2) Apply all events to current confirmed state:
// -----------------------------------------------
World *world = World::getWorld();
int current_time = m_confirmed_state_time;
bool has_state = count > 0;
while(count > 0)
{
// 2.1) Decode the event in the message
// ------------------------------------
ItemEventInfo iei(buffer, &count);
// 2.2) If the event needs to be applied, forward
// the time to the time of this event:
// ----------------------------------------------
int dt = iei.getTicks() - current_time;
// Skip an event that are 'in the past' (i.e. have been sent again by
// the server because it has not yet received confirmation from all
// clients.
if(dt<0) continue;
// Forward the saved state:
if (dt>0) forwardTime(dt);
// TODO: apply the various events types, atm only collection
// and new items are supported.
if(iei.isItemCollection())
{
int index = iei.getIndex();
// An item on the track was collected:
AbstractKart *kart = world->getKart(iei.getKartId());
// The world clock was set by the RewindManager to be the time
// of the state we are rewinding to. But this confirmed collection
// event happened in the past (we are replaying item events since
// the last confirmed state in order to get a new confirmed state).
// So we need to reset the clock to the time at which this event
// happened so that (e.g.) kart can use the right time (for
// example, bubble gum torque depends on time, and would be wrong
// otherwise resulting in stuttering).
int old_time = world->getTicksSinceStart(); // Save time we rewind to
world->setTicksForRewind(iei.getTicks()); // Set time of event
collectedItem(m_confirmed_state[index], kart);// Collect item
world->setTicksForRewind(old_time); // Set time to rewind-to
if (m_confirmed_state[index]->isUsedUp())
{
delete m_confirmed_state[index];
m_confirmed_state[index] = NULL;
}
}
else if(iei.isNewItem())
{
AbstractKart *kart = world->getKart(iei.getKartId());
ItemState *is = new ItemState(iei.getNewItemType(), kart,
iei.getIndex() );
is->initItem(iei.getNewItemType(), iei.getXYZ());
if (m_confirmed_state.size() <= is->getItemId())
{
m_confirmed_state.push_back(is);
}
else
{
if (m_confirmed_state[is->getItemId()] == NULL)
m_confirmed_state[is->getItemId()] = is;
else
{
*m_confirmed_state[is->getItemId()] = *is;
delete is;
}
}
}
current_time = iei.getTicks();
} // while count >0
// Inform the server which events have been received (if there has
// been any updates - no need to send messages if nothing has changed)
if (has_state)
{
if (auto gp = GameProtocol::lock())
gp->sendItemEventConfirmation(world->getTicksSinceStart());
}
// Forward the confirmed item state to the world time:
int dt = world->getTicksSinceStart() - current_time;
if(dt>0) forwardTime(dt);
// 3. Restore the state to the current world time:
// ===============================================
for(unsigned int i=0; i<m_confirmed_state.size(); i++)
{
Item *item = i < m_all_items.size() ? m_all_items[i] : NULL;
const ItemState *is = m_confirmed_state[i];
if (is && item)
*(ItemState*)item = *is;
else if (is && !item)
{
Vec3 xyz = is->getXYZ();
Item *item_new = dropNewItem(is->getType(), is->getPreviousOwner(),
&xyz);
if (i != item_new->getItemId())
{
// The server has this item at a different index in the list
// of all items, which means the client has an incorrect
// item at the index given by the server - delete that item
Log::info("nim", "about to delete item with not matching index i %d item %d",
i, item_new->getItemId());
if(m_all_items[i])
deleteItem(m_all_items[i]);
m_all_items[item_new->getItemId()] = NULL;
m_all_items[i] = item_new;
item_new->setItemId(i);
}
item_new->setPredicted(false);
item_new->setDeactivatedTicks(is->getDeactivatedTicks());
*((ItemState*)m_all_items[i]) = *is;
}
else if (!is && item)
{
Log::info("nim", "About to delete item index %d i %d",
item->getItemId(), i);
deleteItem(m_all_items[i]);
}
}
// Now we save the current local
m_confirmed_state_time = world->getTicksSinceStart();
} // restoreState